“There is shock in our community, just like in any community when you lose a little one like this, and a lot of thoughts and prayers are going the family’s way right now,” he said.

Cyrus Williams, 70, is a Vietnam War veteran and Indian carver who lives on property along Marine Drive NE near where the children were found Monday.

The wooded terrain has been a place where homeless people have taken refuge in the past, he said.

A few weeks ago, Williams and his family took in the woman and her children, as they have helped other people over the years when they have needed a roof over their heads.

“I’m always out of bread and I’m always out of milk,” he said.

The woman and her young children lived temporarily in a camper trailer on the property.

“We let her stay here for about a week or so,” Williams said.

The woman indicated that she had found another living arrangement, he said.

Just after midnight, a woman was booked into Snohomish County Jail by Tulalip tribal police in connection with the case.

The woman, 36, was being held Tuesday for investigation of criminal endangerment and failure to support or care for a dependent person.

The Herald is not naming her because of limited access to information about the status of her case. She was booked into jail for offenses under tribal statutes, so documents detailing reasons for her arrest were not available under state records laws.

The woman also was booked on a warrant from Marysville police in connection with a September traffic stop. Police alleged that she was driving without a license, court papers show.

She was due to be arraigned Sept. 25 but failed to appear. The warrant was issued the next day.

On Tuesday afternoon, a handful of police cars remained at the scene, which was set off from a busy stretch of road, behind a cyclone fence.

The FBI’s Seattle office on Tuesday confirmed that agents were assisting with processing the scene and tracking down leads. Federal agents often offer assistance with investigations on tribal land.

Social workers with the Children’s Administration branch of the state Department of Social and Health Services also were working closely with tribal police, spokeswoman Chris Case said Tuesday.

They plan to conduct a child fatality review because Child Protective Services had investigated a complaint about Chantel’s care within the past year.

“Anytime you’re dealing with a family, particularly when you’re in a situation when there’s a sudden death, we have to be really careful about releasing information to make sure it’s completely factual,” she said. “This is an evolving situation.”

It typically takes about six months for the state to issue any conclusions from a child fatality review.

The Snohomish County Medical Examiner’s Office on Tuesday also was investigating the child’s cause of death, a spokesman said.

Snohomish County prosecutors typically handle serious felony cases involving people living on the reservation, whether or not they are tribal members. As of Tuesday afternoon, county prosecutors were not involved in this case, said Joan Cavagnaro, the county’s chief criminal deputy prosecutor.

The girls’ mother is an enrolled member of the Tulalip Tribes, but the children had not yet been enrolled, Sheldon said.